A Proteoglycanok szerepe a Spondylitis Ankylopoeticaban = The Role of Proteoglycans in Ankylosing Spondylarthropathy

Kutatásunk egyik alapvető kérdésfeltevése az volt, hogy vajon milyen összefüggést találhatunk a proteoglikánok (aggrekán) és a mozgásszervi autoimmun betegségek között, ill. ezen belül is a gerincet érintő spontdylitisek között. Állatkísérletekkel (egér immunizálás aggrekánnal) vizsgáltuk a kialakuló immunválaszt, az ízület és a gerinc részvételét ezen folyamatokban. Egyértelművé vált, hogy a genetikai háttér meghatározza a betegségre való hajlamot, de azt teljes egészében nem determinálja. Meglepő és fontos eredményünk, hogy az arthrodialis ízületek és a spondylitis nem mindig egyszerre megjelenő betegségek, sokkal inkább különálló entitások, melyek genetikai háttere is különbözik. A spondylitisek, valamint az ún. failed back syndromának, ugyanakkor sokkal nehezebben modellezhető és után vizsgálható a humán előfordulása. Az általunk gyűjtött nagy számú minta vizsgálata során nem sikerült egyértelmű összefüggést találni a serumban megjelenő autoantitestek, ill. a betegség megjelenése és súlyossága között. | The basic theory of our research was that proteoglycans (more specifically aggrecane) plays a pivotal role in the autoimmune diseases of the musculoskeletal system, in particular in the inflammation of the spine. Our animal model of arthritis (murine immunized with aggrecane)has been found extremely useful for this purpose, and the role and importance of distinct immunological reactions were identified in the inflammation of the joints and the spine. Genetic background of the mice was found to be of paramount importance yet it was not the exclusive predicting factor in the development of the disease. Surprisingly, we found that spondylitis and the inflammation of the arthrodial joints do not coincide constantly, and it appears that this two diseases represents rather two utterly distinct entity. The assessment of the human immunological diseases, on the other hand, is way more demanding and in spite of our greatest effort we have not been able to identify any correlation between the occurrence and the severity of these human diseases and the presence and concentration of the autoantibodies against the cartilage constituents

“Platelet-associated regulatory system (PARS)” with particular reference to female reproduction

BACKGROUND: Blood platelets play an essential role in hemostasis, thrombosis and coagulation of blood. Beyond these classic functions their involvement in inflammatory, neoplastic and immune processes was also investigated. It is well known, that platelets have an armament of soluble molecules, factors, mediators, chemokines, cytokines and neurotransmitters in their granules, and have multiple adhesion molecules and receptors on their surface. METHODS: Selected relevant literature and own views and experiences as clinical observations have been used. RESULTS: Considering that platelets are indispensable in numerous homeostatic endocrine functions, it is reasonable to suppose that a platelet-associated regulatory system (PARS) may exist; internal or external triggers and/or stimuli may complement and connect regulatory pathways aimed towards target tissues and/or cells. The signal (PAF, or other tissue/cell specific factors) comes from the stimulated (by the e.g., hypophyseal hormones, bacteria, external factors, etc.) organs or cells, and activates platelets. Platelet activation means their aggregation, sludge formation, furthermore the release of the for-mentioned biologically very powerful factors, which can locally amplify and deepen the tissue specific cell reactions. If this process is impaired or inhibited for any reason, the specifically stimulated organ shows hypofunction. When PARS is upregulated, organ hyperfunction may occur that culminate in severe diseases. CONCLUSION: Based on clinical and experimental evidences we propose that platelets modulate the function of hypothalamo-hypophyseal-ovarian system. Specifically, hypothalamic GnRH releases FSH from the anterior pituitary, which induces and stimulates follicular and oocyte maturation and steroid hormone secretion in the ovary. At the same time follicular cells enhance PAF production. Through these pathways activated platelets are accumulated in the follicular vessels surrounding the follicle and due to its released soluble molecules (factors, mediators, chemokines, cytokines, neurotransmitters) locally increase oocyte maturation and hormone secretion. Therefore we suggest that platelets are not only a small participant but may be the conductor or active mediator of this complex regulatory system which has several unrevealed mechanisms. In other words platelets are corpuscular messengers, or are more than a member of the family providing hemostasis

A novel assay for apoptosis: Flow cytometric detection of phosphatidylserine expression on early apoptotic cells using fluorescein labelled Annexine V

In the early stages of apoptosis changes occur at the cell surface, which until now have remained difficult to recognize. One of these plasma membrane alterations is the translocation of phosphatidylserine (PS) from the inner side of the plasma membrane to the outer layer, by which PS becomes exposed at the external surface of the cell. Annexin V is a Ca2+ dependent phospholipid-binding protein with high affinity for PS. Hence this protein can be used as a sensitive probe for PS exposure upon the cell membrane. Translocation of PS to the external cell surface is not unique to apoptosis, but occurs also during cell necrosis. The difference between these two forms of cell death is that during the initial stages of apoptosis the cell membrane remains intact, while at the very moment that necrosis occurs the cell membrane looses its integrity and becomes leaky. Therefore the measurement of Annexin V binding to the cell surface as indicative for apoptosis has to be performed in conjunction with a dye exclusion test to establish integrity of the cell membrane.\ud \ud This paper describes the results of such an assay, as obtained in cultured HSB-2 cells, rendered apoptotic by irradiation and in human lymphocytes, following dexamethasone treatment. Untreated and treated cells were evaluated for apoptosis by light microscopy, by measuring the amount of hypo-diploid cells using of DNA flow cytometry (FCM) and by DNA electrophoresis to establish whether or not DNA fragmentation had occurred. Annexin V binding was assessed using bivariate FCM, and cell staining was evaluated with fluorescein isothiocyanate (FITC)-labelled Annexin V (green fluorescence), simultaneously with dye exclusion of propidium iodide (PI) (negative for red fluorescence). The test described, discriminates intact cells (FITC−/PI−), apoptotic cells (FITC+/PI−) and necrotic cells (FITC+/PI+). In comparison with existing traditional tests the Annexin V assay is sensitive and easy to perform. The Annexin V assay offers the possibility of detecting early phases of apoptosis before the loss of cell membrane integrity and permits measurements of the kinetics of apoptotic death in relation to the cell cycle. More extensive FCM will allow discrimination between different cell subpopulations, that may or may not be involved in the apoptotic process

Analysis of apoptosis on chip - Why the move to chip technology

Apoptosis refers to a specific form of programmed cell death, which guarantees the welfare of the whole organism through the elimination of unwanted cells. The duration of apoptosis is short, involves single cells with morphological changes only after the point of no return, ending with phagocytosis without reaction in the neighbour cell. A number of techniques exist to measure cell death, but we still looking for a simple, specific and sensitive technique which offers the possibility to measure apoptosis on single cell level, without staining, in real time, with high-throughput. The Lab-in-a-Cell concept by using chip technology offers such a tool

Blood-brain barrier (BBB): an overview of the research of the blood-brain barrier using microfluidic devices

The blood-brain barrier (BBB) is a unique feature of the human body, preserving brain homeostasis and preventing toxic substances to enter the brain. However, in various neurodegenerative diseases, the function of the BBB is disturbed. Mechanisms of the breakdown of the BBB are incompletely understood and therefore a realistic model of the BBB is essential. This chapter highlights the anatomy and physiology of the BBB and gives an overview of the current available in vitro models to study the BBB in detail. Proof-of-concept work of BBB-on-Chips are described. Additionally, examples are given to optimize the present devices by engineering the microenvironment to better mimic the in vivo situation. This combination of biomedical science and micro-engineering will generate exciting new results in the field of neurovascular biology